There's no genre of book more morbidly fascinating than true crime nonfiction books. They've got all the scare factor of a psychological thriller or horror story, but with the added factor that everything in the book actually happened. Reading a true crime novel is like slowing down in traffic to look at a car accident; you know you shouldn't be doing it, but you just can't look away. True crime novels are full of the most terrible things human beings are capable of doing — and that's what makes them so captivating. That's why we all listened to every episode of Serial, and binge-watched the whole of Making a Murderer. When it comes to real-life stories that read like fiction, we just can't help ourselves.

We've all heard of Helter Skelter and In Cold Blood and The Stranger Beside Me. These are the books that kick-started the true crime genre, and terrified the population with stories of cults and mass-murders and serial killers. But there are even more true crime novels that you probably don't have on your bookshelf yet, and these are even creepier than anything you've read before. These 13 books might not go down well with your book club, but if you've got a passion for the dark and disturbing rabbit hole of true crime writing, then you're going to love them.

1'A Death in California' by Joan Barthel

Over the course of one long, nightmarish weekend, Hope Masters was held captive and tormented by the man who had just murdered her fiancé. In an attempt to save her own life, Hope decided to talk calmly and even jokily to her tormenter, hoping that this would dissuade him from murdering her. But what happened next was unimaginable: Hope began to fall in love with him.

5'The Unspeakable Crimes of Dr. Petiot' by Thomas Maeder

Dr Marcel Petiot was, from the outside, a hero of German-occupied Paris, offering those wanted by the Germans a safe escape route to South America. But the truth is much more gory: Dr Petiot was a serial killer, murdering the people that he lured to his house under this pretense. The remains of 23 people were found in his house, but the true number of his victims is still unknown.

6'Under the Banner of Heaven' by Jon Krakauer

Jon Krakauer is more famous for his other true crime novel Into Thin Air, but the underrated Under the Banner of Heaven is every bit as sinister. It's about the double murders committed by Mormon fundamentalists Ron and Dan Lafferty, of their sister-in-law Debra and her infant daughter Erica — a murder they believed they had been commanded to carry out by God.

9'The Wicked Boy: The Mystery of a Victorian Child Murderer' by Kate Summerscale

One morning, 13-year-old Robert Coombes and his 12-year-old brother Nattie told the neighbors that their father had gone to sea, and set out to watch a cricket match at Lord's. The boys went on to spend ten days living luxuriously, pawning their parents' valuables to pay for trips to the seaside and the theater, before the neighbors started to notice a strange smell emanating from the house. When police were called to investigate, they discovered that the boys had been sharing the house with the decomposing body of their mother, whom they had stabbed to death ten days before.

10'A Daughter's Deadly Deception' by Jeremy Grimaldi

Jennifer Pan seemed like the model daughter: studying to become a pharmacist, and volunteering at a hospital for sick children. But when her father discovered that she had been lying about everything from her high school grades to her fictitious apartment, and was instead spending her days with her high school boyfriend, Jennifer's parents restricted her to the house to study for university. But neither of them could have suspected what Jennifer would do next — a plot which left her mother dead and her father gravely injured.

11'Whoever Fights Monsters' by Robert K. Ressler and Tom Schactman

In his 20 years working for the FBI, Robert K. Ressler has come face-to-face with many of America's most terrifying killers. His work tracking serial killers by pyscho-analysing evidence left at the crime scene might sound like something straight out of The Silence of the Lambs — and in fact, Robert K. Ressler advised Thomas Harris on writing that very novel. In this book, Ressler takes his readers on the hunt for today's most dangerous psychopaths.

13'Lost Girls' by Robert Kolker

There's a serial killer at large on Long Island: the Craiglist Ripper is believed to have murdered 10 to 17 people over a period of 20 years. In Lost Girls, reporter Robert Kolker explores the dangers of being an online escort, and a critique of the many ways society and the police let the victims down.